Stem Cells May Cause Vascular Disease
Song Li, professor of bioengineering and a researcher at the UC Berkeley Stem Cell Center, and his colleagues studied a stem cell type called a multipotent vascular stem cell. The study showed that contrary to the belief that smooth muscle cells found in the walls of the blood vessels, fat and cholesterol, is the main culprit for clogged arteries. When blood vessels are blocked, this can cause strokes and heart attacks. Li’s work shows that the stem cells are really the cause and should be the main focus of treatment options for many types of vascular disease. The study was published in the Native Communications journal last June 5.
Song Li, who is the principal investigator of the study, said that the evidence for vascular diseases can be found with the stem cells and this discovery will change a lot of known therapies and medical procedures for vascular disease. The discovery that stem cells have a hand in the hardening of the arteries like atherosclerosis can be the doorway to further research in this area.
Dr. Deepak Srivastava, a Cardiovascular Disease researcher at UC San Francisco, provided a number of vascular tissues from mice for the study. He said that the study is significant since treating vascular stem cells would be an easier method than going for the smooth muscle cells of the vessel walls.
The common notion that the development of artery-blocking plaque comes from the body’s reaction to damaged vessels because of the lipoproteins which are bad cholesterol that people get from their diet. The damage builds up the white blood cell for form scar tissues in the vessel which obstructs blood flow. Neointima is the medical terms for such scar tissues in the walls of blood vessels. It was concluded that due to the stop of smooth muscle cell growth, the inflammation that happens, they revert and contribute to the plaque formation.
So far no studies have been made to look into the de-differentiation that happens thus Li and his team remains doubtful that this really is the case. They resorted to studying mice to look into this process. They injected an agent into the mice so that the smooth muscle cells would be colored green under the microscope. They took samples of the middle layer of the cell since the matured smooth muscle cells accounted for 90% of the blood vessel cells.
One month after cell expansion, experts saw an increase by three times in terms of size by the smooth muscle cells along wth stress fibers. There were no cells that were green thus it showed that the build-up was not caused by the smooth muscle cells.
Zhenyu Tang, one of the study’s co-authors, said that there was another type of cell that they found. Aijun Wang, a former researcher in Li's lab, also mentioned that they did a series of tests to determine what these cells were and it showed that stem cells were involved.
As they continued with their tests, they discovered that vascular stem cells are multipotent. This means that they are capable of differentiation from other cell types. This is the reason why they were never identified in vessel blood clogs.
As time goes on for a vascular disease, the vessels become hard and brittle. Li explains that the stem cells have the ability to develop into a cartilage or bone and thus can calcify in the blood vessels. Contact a vein specialist if you are worried about the health of your veins and vascular disease.